P3

• Static electricity is the build up of charge on insulating materials
• When two objects are rubbed together, the friction can cause electrons to move from one object onto the other. This can lead to a build up of charge. 

  However, this doesn't work for friction between two conducting materials as the electrons would just flow straight back again.
• A large build up of charge on an object can cause a large potential difference between the object and the earth.

  The large potential difference could allow electrons to jump through the air to earth, causing a spark. 
• The electric field is stronger the closer you are to the charged particle
• A strongly charged object can ionise the air, which means the air:


  Conducts electricity

  Loses some of its electrons
• Current is a measure of the flow of electrons around a circuit
• battery

  
• Potential difference is the force driving the flow of electrons around a circuit
• Resistance is everything that resists or opposes the flow of electrons in a circuit
• DIODES


  Only allow current to flow one way around a circuit